<?php

namespace App\Http\Controllers\Api\Admin\IpPool\Concerns;

use App\Services\IpPool\IpPoolSheetImporter;
use App\Models\IpPool;
use App\Models\ModuleIpAddress;
use App\Models\ModuleNetwork;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

trait ManagesIpPoolBulkActions
{
    public function bulkUpdateGateway(Request $request): JsonResponse
    {
        $request->validate([
            'ids'      => 'required|array|min:1',
            'ids.*'    => 'integer',
            'gateway'  => 'required|string|max:45',
        ]);

        $pools = IpPool::whereIn('id', $request->ids)->get(['id', 'ip_address', 'module_network_id']);

        if ($pools->isEmpty()) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy IP Pool nào'], 404);
        }

        DB::beginTransaction();
        try {
            IpPool::whereIn('id', $pools->pluck('id'))->update(['gateway' => $request->gateway]);

            // Mirror into module_ip_address, grouped by network to keep this to a handful of queries.
            foreach ($pools->groupBy('module_network_id') as $networkId => $group) {
                ModuleIpAddress::whereIn('ip', $group->pluck('ip_address'))
                    ->where('module_network_id', $networkId)
                    ->update(['gateway' => $request->gateway]);
            }

            DB::commit();
        } catch (\Exception $e) {
            DB::rollBack();
            return response()->json(['error' => true, 'message' => $e->getMessage()], 500);
        }

        return response()->json([
            'error'   => false,
            'message' => "Đã cập nhật gateway cho {$pools->count()} IP",
            'updated' => $pools->count(),
        ]);
    }

    public function bulkDelete(Request $request): JsonResponse
    {
        $request->validate([
            'ids'   => 'required|array|min:1',
            'ids.*' => 'integer',
        ]);

        $ids  = $request->ids;
        $pools = IpPool::whereIn('id', $ids)->get();

        if ($pools->isEmpty()) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy IP Pool nào'], 404);
        }

        // Block deletion if any IP is currently assigned
        $inUseIps = ModuleIpAddress::whereIn('ip', $pools->pluck('ip_address'))
            ->where('status', 1)
            ->pluck('ip')
            ->toArray();

        if (!empty($inUseIps)) {
            return response()->json([
                'error'   => true,
                'message' => 'Không thể xoá — các IP sau đang được gán cho máy chủ: ' . implode(', ', $inUseIps),
            ], 422);
        }

        foreach ($pools as $p) {
            ModuleIpAddress::where('ip', $p->ip_address)
                ->where('module_network_id', $p->module_network_id)
                ->delete();
        }

        $deleted = IpPool::whereIn('id', $ids)->delete();

        return response()->json([
            'error'   => false,
            'message' => "Đã xoá {$deleted} IP Pool thành công",
            'deleted' => $deleted,
        ]);
    }

    public function importPreview(Request $request, IpPoolSheetImporter $importer): JsonResponse
    {
        $request->validate(['file' => self::IMPORT_FILE_RULE]);

        return response()->json(['error' => false, 'data' => $importer->preview($request->file('file'))]);
    }

    public function import(Request $request, IpPoolSheetImporter $importer): JsonResponse
    {
        $request->validate(['file' => self::IMPORT_FILE_RULE]);

        $summary = $importer->import($request->file('file'));

        return response()->json([
            'error'   => false,
            'message' => "Đã thêm {$summary['create']}, cập nhật {$summary['update']} IP"
                . ($summary['error_count'] ? ", bỏ qua {$summary['error_count']} dòng lỗi" : ''),
            'data'    => $summary,
        ]);
    }

    /**
     * Backfill/repair the module_ip_address mirror for every ip_pools row.
     * Existing mirror rows only get gateway/netmask refreshed — status/vm_name
     * (assigned VM state) is left untouched. Missing rows are created with
     * status derived from the current ip_pools.status.
     */
    public function sync(): JsonResponse
    {
        $created  = 0;
        $updated  = 0;
        $hostByNet = ModuleNetwork::pluck('module_host_id', 'id');

        IpPool::whereNotNull('module_network_id')->chunkById(500, function ($pools) use (&$created, &$updated, $hostByNet) {
            foreach ($pools as $pool) {
                $hostId  = $hostByNet[$pool->module_network_id] ?? null;
                $netmask = $pool->netmask ?: '255.255.255.0';

                $mia = ModuleIpAddress::where('ip', $pool->ip_address)
                    ->where('module_network_id', $pool->module_network_id)
                    ->first();

                if ($mia) {
                    $mia->update([
                        'module_host_id' => $hostId,
                        'gateway'        => $pool->gateway,
                        'netmask'        => $netmask,
                    ]);
                    $updated++;
                } else {
                    ModuleIpAddress::create([
                        'ip'                => $pool->ip_address,
                        'module_network_id' => $pool->module_network_id,
                        'module_host_id'    => $hostId,
                        'gateway'           => $pool->gateway,
                        'netmask'           => $netmask,
                        'status'            => $pool->status === 'assigned' ? 1 : 0,
                    ]);
                    $created++;
                }
            }
        });

        return response()->json([
            'error'   => false,
            'message' => "Đã đồng bộ: tạo mới {$created}, cập nhật {$updated}",
            'created' => $created,
            'updated' => $updated,
        ]);
    }
}